Ask HN: Could Intel have challenged x86 with 64-bit RISC instead of Itanium?

Sure.

But to have any chance in the marketplace, the new "iRISC64" architecture would have to actually ship working chips, with decent price/performance ratios, in a timely manner. The #1 reason for Itanium failing was Intel's disastrous inability to do that - https://en.wikipedia.org/wiki/Itanium#Design_and_delays:_199...

Meanwhile, actual x86 chips were shipping - in volume, with fast-improving price/performances ratios. And industry insiders, who were familiar with Intel's long history of great-sounding, non-x86 architectures - which turned out to be crap for ~99% of use cases - were quietly filing "Itanium" into the "another one of those" pigeonhole.

Wasn't a big reason that success of Itanium relied heavily on compiler technology to make effective use of the VLIW architecture?

And that even with compiler support, it didn't manage to give Itanium systems a (big enough) edge over other systems?

Combined with product delays & other issues.

What makes more sense to me is Intel's proposal to drop some 16/32 bit legacy cruft from x86-64 ("x86-S"). Perhaps even drop user-mode 32 bit support? (depending on how much it simplifies implementations, and/or improves performance/W).

Haven't heard about this recently. But maybe it's up for introduction later on?

This would keep support for existing software (mostly) intact. But still cut out a nice chunk of x86 ugliness.

Itanium was a 64-bit RISC architecture

Had Intel said something like Apple has each time they have made a CPU change (68k to PPC to x86 to ARM): "here is the new thing; we will support a fat binary model for a 'while'; move to the new thing", Itanium (which, from a technical viewpoint should have blown the ever-loving PANTS off x86) would have [probably] 'won'

Or we would have an even-more splintered CPU space - x86-64 from AMD, ARM, POWER, Itanium, etc

But they did not

They release the Itanic as a side-by-side with their existing CPU lines, which encouraged AMD to develop AMD64, and more-or-less forever broke Intel's utter dominance of the desktop and server space

x86 has survived, not despite its flukes, but because of them. The effort to learn around them increased the sunk costs that created an emotional block against moving off the platform.

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